Script code currently cannot invoke COM interface methods on exposed RCWs. This is an issue because the OS includes many useful COM objects. Besides, if it implements IDispatch, it should be scriptable, period.
Comments: Fixed in [ClearScript 5.4](https://clearscript.codeplex.com/releases/view/135637).
Comments: Fixed in [ClearScript 5.4](https://clearscript.codeplex.com/releases/view/135637).